Process analysis and operation points of connecting rod forgings:
1. Process analysis.
The forgings of the connecting rods have large cross-sections and have I-shaped cross-sections. The forgings have a mass of 0.92kg and the quality tolerance is 30g. The size and technical requirements are relatively high. The annual requirements for forgings are over 1 million pieces.
The section of forgings varies greatly. It is unreasonable to use the hot forging pressure mechanism blank, but the blanking on the free forging hammer can not adapt to the large-scale automatic production, and the preform quality is not stable, so the roll forging mechanism blank is selected. The effect is better. The process uses one forging two connecting rods, the process forging process card, and the forming process of the blank. After the billet is rolled four times, it is flattened on a hot forging press, which can remove the scale at both ends while allowing the billet to be placed smoothly on the pre-forging die. The bending and twisting of the forgings are required to be controlled within 0.2 mm. Forgings can be cold-spun after shot peening if necessary.
2. Operating points.
1) The blanking process of the connecting rod forgings is operated by the robot of the automatic control system. The operator should carefully carry out the random inspection of each process, and must use medium frequency heating to prevent the decarburization layer on the forging surface.
2) After the roll forging, the blank size should be checked strictly according to the process drawing, and it is found that the warping should adjust the roller in time.
3) Before die forging on hot forging press, the installation and debugging of the mold should meet the requirements of the forging step. The trial parts should be inspected strictly according to the technical requirements of the forgings, and then the molds should be tightened according to the requirements to prevent the formal production. Loose fasteners cause an increase in the amount of forging displacement. The trial forging of forgings should include the entire process of die forging.